New Mexico school gunman was ex-student investigated by FBI

TAOS, New Mexico (Reuters) - A gunman who killed two students at a New Mexico high school and then took his own life was a former student who was investigated by the U.S. Federal Bureau of Investigation last year after he asked online about buying weapons for a mass shooting, officials said on Friday.

Authorities identified the shooter in Thursday's attack as 21-year-old William Atchison, who worked at a gas station in Aztec, New Mexico, and was an enthusiast of active shooter gaming websites.

"He was a single coward shooter," San Juan County Sheriff Ken Christesen said at a news conference by law enforcement. "It's important to understand how focused he was, how deranged he was, in his intent."

The shooting occurred shortly after 8 a.m. on Thursday at the high school in Aztec, a town of 6,000 people about 200 miles (320 km) northwest of Santa Fe and 20 miles (32 km) from the Navajo Nation reservation.

Atchison disguised himself as a student, entered the school as students got off buses, and was in a bathroom preparing for the shooting when Francisco Fernandez, a pupil at the school known for his computer skills, entered the restroom, officials said.

Atchison shot Fernandez, then exited the bathroom and shot cheerleader Casey Jordan-Marquez in the hallway, said New Mexico State Police Chief Pete Kassetas.

Atchison fired randomly in the hallway before entering a computer lab and firing through a wall at students barricaded inside a closet, Kassetas said. Atchison likely shot himself shortly afterwards as police entered the school, he added.

Police found a thumb drive on Atchison's body that contained a Dec. 7 message indicating he was unhappy with work and life, and he planned to attack a school.

"If things go according to plan, today would be when I die," the message read.

In March 2016, Atchison was interviewed by the FBI, which had acted on a tip about a comment he made on an online gaming site.